1. Field of the Invention.
The present invention relates to coal burners utilizing underfeed stokers, and incorporating improved burner construction.
2. Description of the Prior Art.
Coal burners and underfeed stokers are well known in the prior art, and many of these burners utilize a rotating ash ring for removal of ashes from the burner body to prevent the build-up of clinkers. For example, U.S. Pat. No. 1,871,653 issued to M. W. Best in August of 1932 shows a rotating fire pot base which is used for aiding in ash removal. This burner device includes an underfeed stoker.
U.S. Pat. No. 1,921,864, issued to Brossman in August of 1933, also shows an underfeed rotary grate stoker that has an ash ring that is rotatably mounted around a central burner body, and the rotating grate aids in the disintegration of clinkers and removal of ashes.
U.S. Pat. No. 2,033,919, issued in March of 1936 to Burton, shows a burner with a central throat member made of discs that are vertically stacked and including a rotating grate surrounding the throat member.
U.S. Pat. No. 2,396,888 to Scholl, issued in March of 1946, shows a stoker fed burning apparatus that includes a plenum chamber for receiving the blower air, and a vertical wall in the burner apparatus that distributes the air, and which includes an ash ring that is oscillated during the time that the burner is in operation and the stoker is being operated.
U.S. Pat. No. 2,455,817, issued to Sherman in December of 1948, also shows an underfeed stoker apparatus having a delivery throat for coal, and an apertured plenum chamber that provides air to the burning mass of coal.
U.S. Pat. No. 2,405,982 to Schweickart et al., issued in August of 1946, illustrates an underfeed stoker that has an ash removal mechanism, air feed, and includes a rotary grate structure that is driven around the central axis of the burner.
Additionally, U.S. Pat. No. 4,007,697 issued to Prill in February 1977, shows a stoker apparatus having a rotating ash ring with a central burner that has a tapered upper burner surface.
A burner construction using parallel plates that are spaced apart in vertical direction as shown in U.S. Pat. No. 2,253,694, issued to Drawz in August of 1941.
Each of the above patents show different burner constructions, including rotating rings, but yet in large in commercial stokers, the need for a device that provides good capacity, adaptability to different sizes to minimize manufacturing costs selectively still persists.